1. Field of the Invention
This invention relates in general to a scissors jack and in particular to an improved drive mechanism.
2. Description of the Prior Art
U.S. Pat. No. 4,802,653 illustrates a scissors-type jack which can be raised and lowered with a folding lug wrench which has a handle that is pivotally connected to a tube that has a hexagonal opening and a hexagonal outer contour. In such jacks, the hexagonal tube fits over the hexagonal hex head on a threaded screw such that as the threaded screw is rotated with the lug wrench, the jack can be raised and lowered.
The hex head of the screw is the same size as the lug nuts and the hex tube of the folding lug wrench fits over the hex head of the screw.
With such prior art scissors jack, it is possible to overload the jack by exerting too much torque on the hex head of the threaded screw of the jack so as to bend or break the jack.